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Instruction Book
Page 24
ondary contacts when in the disconnected position. The
structure mounted secondary contact blocks are perma-
nently mounted and cannot be moved out for direct con-
nection with the breaker mounted secondary contacts.
b) For the behind the door configuration, carefully load
the breaker into the structure until it reaches the Test
position. For the flush mounted configuration, carefully
move the breaker toward the structure until it reaches
the Test position.
c) If a lifting yoke was used to move and/or load the
breaker, remove the yoke at this time.
d) For the behind the door configuration, manually
engage the secondary contact blocks by pulling the
movable blocks forward as far as possible. For the flush
mounted configuration, connect the test cable to both
the breaker and structure secondary contact blocks. As
soon as control power is available, the motor will
charge the closing springs.
e) Close and trip the breaker several times to verify the
closing and tripping operations
f) Conclude by closing the breaker.
4-9 BREAKER / COMPARTMENT INTERFACE CHECK
The following interlocks are provided to insure safe and
correct operation:
a) Floor Tripping and Spring Release Interlock:
This optional interlock closes and trips the breaker if the
closing springs are charged as the breaker is moved
from the Test position to the Withdrawn position and
vice versa.
b) Levering Interlocks:
1. Carriage Assembly Version: This version is used for
single tier switchgear configurations. The levering
crank can only be engaged when the breaker is
open and the shoot bolt lever is lifted (Figure 4-1b)
The breaker will not close manually or electrically
while the levering crank is engaged.
2. Cradle Assembly Version: This version is used for
double tier switchgear configurations. The levering
crank can only be engaged when the breaker is
open and the horizontal shoot bolts are engaged
(fully extended). The breaker will not close manually
or electrically while the levering crank is engaged.
c) Anti-Close Interlock: This interlock prevents releasing
the closing springs electrically or manually if the breaker
is already closed (drawout and fixed configurations).
d) Anti-Latch Interlock: This interlock prevents the
breaker from being closed between the Connected and
Test positions.
e) Shutter Drive Interlock:
The metallic switchgear shutters are independently
operated permitting them to be locked in the open posi-
tion for servicing the primary disconnects. The locking
system is disabled when the breaker is being connected
permitting the shutters to operate in the normal manner.
f) Earthing Drive Interlock:
If the switchgear is equipped with an earthing switch,
the breaker can only be inserted into the switchgear if
the earthing switch is open.
Check for the correct operation of the interlocks just
described by starting with the breaker in the Test posi-
tion and completing the following steps:
Step 1: Engagement of Levering Crank:
1. For the single tier configuration carriage assembly
version, the shoot bolt should be fitted into the first
slot of the interlock plate located on the floor of the
switchgear. Charge the closing springs and close
the breaker. The slider cannot be pushed far
enough to engage the levering crank.
2. For the double tier configuration cradle assembly
version, the horizontal shoot bolts should be fitted
into the slots of interlock plates located at the sides
of the switchgear. Charge the closing springs and
close the breaker. The slider cannot be pushed far
enough to engage the levering crank.
Step 2 :
Open the breaker, engage the levering crank and lever
the breaker into the Connected position. Remove the
levering crank.
Step 3:
Close the breaker. The motor starts charging the closing
springs if control power is available.
Step 4:
Open the breaker, engage the levering crank and
attempt to close the breaker manually or electrically.
The breaker will go trip free (spring discharge but break-
er does not close).
Step 5:
Lever the breaker out approximately half way towards
the Test position. Remove the levering crank and
attempt to close the breaker by pushing the manual
close button. The breaker will go trip free. Lever the
breaker all the way into the Test position. The sec-
ondary disconnects will disengage automatically.
IB131009EN
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